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Sphenodontida
Rhynchocephalia (; ) is an order of lizard-like reptiles that includes only one living species, the tuatara (''Sphenodon punctatus'') of New Zealand. Despite its current lack of diversity, during the Mesozoic rhynchocephalians were a diverse group including a wide array of morphologically distinct forms. The oldest record of the group is dated to the Middle Triassic around 238 to 240 million years ago, and they had achieved a worldwide distribution by the Early Jurassic. Most rhynchocephalians belong to the group Sphenodontia ('wedge-teeth'). Their closest living relatives are lizards and snakes in the order Squamata, with the two orders being grouped together in the superorder Lepidosauria. Many of the niches occupied by lizards today were held by sphenodontians during the Triassic and Jurassic, although lizard diversity began to overtake sphenodontian diversity in the Cretaceous, and they had disappeared almost entirely by the beginning of the Cenozoic. While the modern tuatara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opisthodontia (reptiles)
Opisthodontia is a proposed clade of sphenodontian reptiles, uniting ''Opisthias'' from the Late Jurassic-earliest Cretaceous of Europe and North America with the Elienodontinae, a group of herbivorous sphenodontians known from the Late Triassic to Late Cretaceous. Description Teeth and diet Like other sphenodonts, opisthodonts had acrodont teeth which grew directly from the bone. They had one row of teeth on the lower jaw and two rows on the roof of the mouth. When processing food, their mandibular teeth would have slid between the outer (maxillary) teeth and inner (palatine) teeth. Some opisthodonts, such as '' Sphenotitan'', also had clusters of small teeth on the pterygoid at the center of the mouth roof. Opisthodont teeth were wide, numerous, and tightly-packed for grinding and shredding tough plant matter. Although wide shredding teeth are also known in a few other sphenodontians, such as ''Clevosaurus'' and ''Pelecymala'', the most diverse and long-lasting group of he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphenodontidae
Sphenodontidae is a family within the reptile group Rhynchocephalia, comprising taxa most closely related to the living tuatara of the genus ''Sphenodon''. Historically the taxa included within Sphenodontidae have varied greatly between analyses, and the group has lacked a formal definition. '' Cynosphenodon'' from the Early Jurassic of Mexico has consistently been recovered as a close relative of the tuatara in most analyses, with the clade containing the two often called Sphenodontinae. The herbivorous Eilenodontinae, otherwise considered part of Opisthodontia, is also sometimes considered part of this family as the sister group to Sphenodontinae. Sphenodontines first appeared during the Early Jurassic, and are characterised by a complete lower temporal bar caused by the fusion of the quadrate/quadratojugal and the jugal The jugal is a skull bone found in most reptiles, amphibians and birds. In mammals, the jugal is often called the malar or zygomatic. It is connected to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brachyrhinodon
''Brachyrhinodon'' (meaning "short nose tooth") is an extinct genus of sphenodontian from the Late Triassic Lossiemouth Sandstone of Scotland. It is related to the tuatara, the only member of its order that is not extinct. ''Brachyrhinodon'' is known from the sandstone quarries near Elgin, and is one of the Elgin Reptiles. Sources * ''Vertebrate Palaeontology'' by Michael J. Benton * ''In the Shadow of the Dinosaurs: Early Mesozoic Tetrapods'' by Nicholas C. Fraser and Hans-Dieter Sues Hans-Dieter Sues (born January 13, 1956) is a German-born American paleontologist who is Senior Scientist and Curator of Vertebrate Paleontology at the National Museum of Natural History of the Smithsonian Institution in Washington, DC. He receiv ... *''The Beginning of the Age of Dinosaurs: Faunal Change across the Triassic-Jurassic Boundary'' by Kevin Padian Triassic lepidosaurs Triassic reptiles of Europe Sphenodontia Prehistoric reptile genera {{triassic-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigmala
''Sigmala'' was a reptile from the Late Triassic. Distribution ''Sigmala'' lived in the . Classification ''Sigmala'' was named a sphenodont by R.L. Carroll in 1988. See also *Lepidosauromorpha *Lepidosauria The Lepidosauria (, from Greek meaning ''scaled lizards'') is a subclass or superorder of reptiles, containing the orders Squamata and Rhynchocephalia. Squamata includes snakes, lizards, and amphisbaenians. Squamata contains over 9,000 species, m ... References Fossils of Great Britain Sphenodontia Triassic lepidosaurs Fossil taxa described in 1986 {{triassic-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sapheosaur
Sapheosaurs are an extinct group of rhynchocephalian reptiles from the Late Jurassic period. "Sapheosaurs" is an informal name for a group of rhynchocephalians closely related to the genus ''Sapheosaurus''. It was first recognized as a group containing multiple genera by Hoffstetter in 1955. The group has sometimes been given a formal taxonomic name as the family Sapheosauridae, although in some analyses this group belongs to the family Sphenodontidae (which also contains the tuatara, the only living rhynchocephalian) and thus cannot be assigned its own family. They were fairly advanced rhynchocephalians which may have had semiaquatic habits. Classification The most well-known members of the group are ''Sapheosaurus'' and ''Kallimodon'', and most phylogenetic analyses on rhynchocephalians only study these two genera as representatives of sapheosaurs. Although a few early phylogenies in the 1990s did not find that these two formed a natural clade, the relation between these two i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diphydontosaurus
''Diphydontosaurus'' is an extinct genus of rhynchocephalian reptile from the Late Triassic of England and Italy. This small animal was related to the living tuatara (''Sphenodon''). It may have grown to a length of . It is more derived than ''Gephyrosaurus'', yet more primitive than ''Planocephalosaurus'', and shares traits with both of them. Description ''Diphydontosaurus'' was a small sphenodontian, measuring up to long. It had long, sharp claws to help it catch its prey, and peg-like piercing teeth to help it eat insects. These features are shared with the other primitive rhynchocephalians ''Gephyrosaurus'' and ''Planocephalosaurus''. Classification ''Diphydontosaurus'' is known from many mostly complete specimens, which means that its classification as a rhynchocephalian is quite certain. In an analysis by Oliver Rahut and colleagues in 2012, it was found that ''Diphydontosaurus'' is the second most basal rhynchocephalian, after ''Gephyrosaurus'', and the most primitive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lamarquesaurus
''Lamarquesaurus'' is an extinct genus of sphenodontian from the Late Cretaceous (Campanian) of Patagonia. It is known from a single species, ''Lamarquesaurus cabazai''. This genus and species is represented by MML-PV-42, a well-preserved right maxillary bone (including 10 teeth of varying completeness). This bone was found at the Cerro Tortuga site near Lamarque, Argentina, which preserves fossils from the Cretaceous Allen Formation. The discoverer of the Cerro Tortuga locality, Tito Cabaza, is the namesake of the species. Description The maxilla is in length; including missing portions it would have been about long if complete. The inner surface of the maxilla is deeply concave but the outer surface has several scattered pits as well as deep facets above the third and fifth teeth. These facets are reminiscent of those which sphenodonts possess on the lower jaw due to abrasion from teeth of the upper jaw, but this cannot be the case in ''Lamarquesaurus'''s maxilla. This is be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleollanosaurus
''Paleollanosaurus'' is an extinct genus of sphenodontid reptile that lived during the Late Triassic (Norian and Rhaetian) of Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel .... References {{Reflist Reptiles described in 2004 Late Triassic animals of Europe Sphenodontia Prehistoric reptile genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polysphenodon
''Polysphenodon'' is an extinct genus of clevosaurine reptile from the Late Triassic Keuper Group of Germany,N. C. Fraser and M. J. Benton. (1989) The Triassic reptiles ''Brachyrhinodon'' and ''Polysphenodon'' and the relationships of the sphenodontids. ''Zoological Journal of the Linnean Society'' 96:413-445 discovered within a borehole at below the surface. The type species, ''P. mulleri'', was described by Otto Jaekel in 1911.Jaekel, O (1911) Die Wierbeltiere. Eine Übersicht über diefossilen und lebenden Formen. ''Borntraeger, Berlin'', 252p The limbs of ''Polysphenodon'' are long relative to the size of the skull and are similar in proportions to some species of ''Homoeosaurus ''Homoeosaurus'' is an extinct genus of sphenodont reptile. It was found in limestone in Bavaria, Germany, as well as in France and the United Kingdom. It was related to the modern tuatara, though it was a considerably more gracile. There were se ...''. This resemblance is considered to be indi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theretairus
''Theretairus'' is a Late Jurassic genus of sphenodont reptile from the Morrison Formation of western North America,Foster, J. (2007). "Table 2.1: Fossil Vertebrates of the Morrison Formation." ''Jurassic West: The Dinosaurs of the Morrison Formation and Their World''. Indiana University Press. pp. 58-59. present in stratigraphic zones 5 and 6.Foster, J. (2007). "Appendix." ''Jurassic West: The Dinosaurs of the Morrison Formation and Their World''. Indiana University Press. pp. 327-329. History and naming The holotype consists of a right mandible and several in-socket teeth from Quarry 9 at Como Bluff, Wyoming where it was excavated by paleontologist William Harlow Reed, who then was working for Othniel Charles Marsh, and it was deposited at the Yale Peabody Museum under YPM VP 13764. The locality comes from strata of the Brushy Basin Member of the Morrison Formation, which also bears other sphenodontians ''Opisthias'' and ''Eilenodon.''Rasmussen, T. E.; Callison, George (198 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pamizinsaurus
''Pamizinisaurus'' is a genus of sphenodontian reptile known from Lower Cretaceous (Albian) Tlayúa Formation of Mexico. A crushed skeleton of a juvenile reptile was found in Tlayua Quarry, in central Mexico. It was named ''Pamizinsaurus tlayuaensis'' by Reynoso in 1997, after the name of the quarry of which it was found. Its skull length is . The fossil was covered in small round osteoderms that could have protected it from predators. Relatives Reynoso (1997) argued that ''Pamizinsaurus'' was a genus of the subfamily Sphenodontinae; grouping it with the modern ''Sphenodon'' (better known as the ''Tuatara''), '' Zapatadon'', '' Cynosphenodon'', ''Homoeosaurus'', ''Sapheosaurus'', and ''Ankylosphenodon ''Ankylosphenodon'' is an extinct species of sphenodontian known from Tepexi de Rodriguez, Mexico. It is known from Early Cretaceous sedimentary deposits from the Tlayua formation. Lifestyle ''Ankylosphenodon'' is thought to have been an aqu ...''. References External ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Triassic
In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided in chronostratigraphy. The Middle Triassic spans the time between Ma and Ma (million years ago). It is preceded by the Early Triassic Epoch and followed by the Late Triassic Epoch. The Middle Triassic is divided into the Anisian and Ladinian ages or stages. Formerly the middle series in the Triassic was also known as Muschelkalk. This name is now only used for a specific unit of rock strata with approximately Middle Triassic age, found in western Europe. Middle Triassic fauna Following the Permian–Triassic extinction event, the most devastating of all mass-extinctions, life recovered slowly. In the Middle Triassic, many groups of organisms reached higher diversity again, such as the marine reptiles (e.g. ichthyosaurs, sauropterygians, thallatosaurs), ray-finned fish and many invertebrate groups like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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